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  1. Core Server
  2. SERVER-17299

Extraneous memory allocations in snappy hurt WiredTiger performance on Windows

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      I have 50 threads bulk inserting 100 <1k documents as fast as Mongo will take them.

      Using the MMap engine doesn't show this behavior. Right now, after running for ~8 minutes, my cpu is sitting at 23% and the insert rate is at 11k/s.

      I don't know if this is expected or not, but it seems like quite a dramatic drop off.

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      I have 50 threads bulk inserting 100 <1k documents as fast as Mongo will take them. Using the MMap engine doesn't show this behavior. Right now, after running for ~8 minutes, my cpu is sitting at 23% and the insert rate is at 11k/s. I don't know if this is expected or not, but it seems like quite a dramatic drop off.

      WiredTiger starts at an insertion rate of 40k/sec, and slows down to 15k/sec within 2 minutes.

      System memory is not exhausted.

      Specifically the CPU% appears to drop from 100% quite quickly and insert times (for the individual bulk inserts) grows.

      MongoStat doesn't appear to show any specific resource limit, nor do I see anything obvious.

      Using the C# driver 2.0.0-beta2.

      Please see https://groups.google.com/forum/#!topic/mongodb-user/DMa24b2TqKM

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            Assignee:
            mark.benvenuto@mongodb.com Mark Benvenuto
            Reporter:
            nickj Nick Judson
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              Created:
              Updated:
              Resolved: